Process of desiccating milk.



J. ROEH. PROCESS OF DEIOOATING MILK. APPLICATION FILED JAN7'15, 1909;

' Patented Jam), 1912.

E H w M W 1 I Q P 3 h1 5% l.lll mw .3 0 A g Q 0 w I MN @N N aw IQ QR F WITNESSES ATTOR/VE Y8 J. ROEH. PROCESS OF DESIGGATING MILK. 'A'PPLfOATION FILED JAN.15. 1909.

2 N B E 0 SE 7/ 9n N E l W JM E d m a P @N N .N* an WITNESSES zn E0670 J. ROBH.

PROCESS OF DESIOCATING MILK. APPLICATION FILED *TAN.15, 1909.

1,014,609. I at n ed Jan.191'2.

3 SHEETS-43331 3.

INVENTOR- Jo fan fioe/a ATTORNEYS 4 thoroughly sterilize n i s JOHN ROEH,

OF SPOKANE, WASHINGTbN, ASSIG'NOR, T0

CORBORATION, OF SPOKANE, WASHINGTON.

PROCESS OF DESICCATING MILK original application filed August 13, 1908, Serial No. 448,302.

Specification of Letters Patent.

Patented Jan. 9, 1912.

Divided and this-application filed January 15, 1909. Serial No. 472,431',

To a whom it may concern Be it known that I, JOHN ROEH, a citizen of the United States, and a resident of Spokanc. in the county of Spokane and State of Washington, have invented a new and Improved Process of Desiccating Milk, of which the following is a full, clear, and exact description.

This invention relates to the treatment of milk for the production of a crystalline or powdered product by the removal of the water therefrom, and is also applicable'to the concentrating or dehydrating of other substances having similar properties.

By means of my improved process, 1 obtainfa milk product in'a light finely subdivided powdered form containing all of the solids including the fatty substances of the milk, in such a condition that they are freely soluble in water to produce a milk similar in all respects to fresh milk, and without necessitating the adding of any foreign substance whatever thereto either before or after the drying or dehydrating action. To secure this product, I take the raw milk in its natural state and spread it very thinly on glass or enameled plates or cylinders, or other hard surfaces, heated to a temperature ranging from 110 to 150'degrees Fahrenheit, and deliver a current of warm artificially dried air against the thin film of milk. During the heating and evaporating of the milk, the latter is repeatedly pressed into engagement with the surface by a rolling action and this heating is continued and the rolling is repeated until the milk is evaporated todryness and is transformed into a hard uniform coa ing, which when scraped from the surface produces a white fl'ufi'y powder. This powder is imme" diately removed, passed thr ugh a fine mesh screen, heated to such a temperature as will the same," and is then packed at once. inairtight receptacles previously sterilized. The milk is not heated to suiiiciently high temperature to cause any chemical change in the cascins, proteids, or other solid constituents, but is spread out in siich a thin film thatin the presence of the current of warm artificially dried air and the action of the heated surface, the water is removed and the solids reduced to a state of complete dryness.

' will now describe. the details of my vof, a portion being broken away;

, truck may be -structed that as it e and as near as possibleto gentry of the two drums.

process, and in order to render the same clear, reference will be had to the accompanying drawings, specification, in which similar characters of reference indicate corresponding parts in all the figures, and in Which- Figure 1 is an end view of an apparatus constructed for the carrying out of my im proved process; Figril is a side view thereand Fig. 3 is a side elevation showing somewhat diagrammatically other portions of the mechanism. ,1

Any suitable form of apparatus may be employed for carrying out my 'improved/ process, but preferably I employ that/disclosed in my prior-applicatidn, Serial Number 448,302, filed August 13, 1908, and of which application this a division. Said apparatus is illustrated/somewhat diagrammatically, as certainK of the details of the CRYSTALIZED MILK 00., a

forming a part of this apparatus have nr/bearing 6n the steps of the process. The apparatus illustrated includes two parallel drums 10 and 11 mounted insuitable'journal boxes and rotated at the same speed in contact with eachother throughout their length. The drums, may be adjusted toward and fromeach other to permit the accumulation of a coating upon the surfaces-of the nal boxes 14 of one of the drums ably mounted for this purpose. 15 serves to gagement irrespective of the thickness of the coating. The drums are hollow and are internally heated in any suitable manner, as, for instance, by the delivery of steam or fluid through the hollow being slidother heating shafts 16, 16 of the two drums Supported above the two drums andextending longitudinally thereof areitwo rails 20, 20, forming a track along which a small moved,v T is truck carries a for the millftor pther liquid to The receptaoe is so conmoves along the track, the milk is delivered to the s rfaces of'the drums. The receptacle prefdrably terminates in a conical, bottom 23 having a spray nozzle 24 located between the two drums tlitir line of ten Thenozzle is of in respect to the; a small receptacle 22 be' desiccated.

such size and so located drums that it can only deliver to drums, one of the our- A spring hold the drums in resilient enportion of the surface at one time, but by moving the truck and receptacle along the track and longitudinally of the drums, all portions of the surfaces of the drums may be reached by the spraying nozzle. Any suitable mechanism may be provided for moving the truck, receptacle and nozzle at a uniform speed in respect to the speed of rotation of the drums. For instance, I may provide the shaft of one of the drums with a pulley 25, which by means of a belt 26, transmits motion to a transverse shaft 28 j ournaled above the drums and adjacent one end thereof. Motion is transmitted from the shaft 28 to a countershaft 29 in any suitable manner, as, for instance, by an intermediate shaft '30 and pairs of intermesh ing bevel gears 31 and 32. The countershaft 29 is'provided with a sprocket wheel over which travels a chain 33, the speed of travel of which is equal to the desired speed of travel of the receptacle 22. The chain is provided with a lug or projection 35 extending through a, vertically-disposed slot 36 in a plate 37 carried by the truck,- the length of the slot being equal to the diameter of the's procket wheels which support the chain 33. As the drums rotate, motionis trans-.

mitted' through the pulley 25 and belt 26 to the upper shaft 28and thence through the shafts 30 and 29 to the chain 33. The move ment of the chain and its lug or' projection 35 causes the truck to travel along the track at the same rate as the chain until the plate reaches one of the sprocket wheels, at which time the lug passes vertically through the slot to the opposite end thereof and the truck is returned in the opposite direct-ion by the continued movement of the chain. The receptacle 22 is thus moved back and forth longitudinally of the rotating drums and at a uniform speed in respect thereto.

In order to secure the objects hereinafter more clearly set forth, there is provided means for automatically shutting off the supply of fluid to the spraying nozzle 24 .while the receptacle is traveling in one direction, and autonmtically opening the valve to permit a flow of fluid to the nozzle while the receptacle is traveling'in the opposite direction. This means includes a valve 38,

adjacent the nozzle, and two pivotally- 'mounted pawls 39 and 40, so mounted in respect to the nozzle that when the receptacle. reaches one end of the drum, one pawl engages with the valve stem, to operate the valve and shut off the supply; while the cngagement of the valve stem with the other pawl operates'said valve stem to open the valve. In this manner, the nozzle sprays liquid upon the surfaces of the drums only while traveling in one direction, the valve being closed during the return movement.

For removing the dried or desiccated material from the surfaces of the drums, I provide scrapers adapted to engage with said surfaces and also adaptedto'travel longitudinally of the drums simultaneously with the receptacle 22 and spraying nozzle. The scrapers forv the two drums are disposed upon opposite sides as the two drums rotate inmpptisite directions, For operating the scrapers, I provide for each of them a chain 42 mounted on sprocket wheels at opposite ends of the corresponding drums and having the same speed asthe chain 33. The chain-42' is driven from the shaft 28 by a chain 41, so that the two chains 33 and 42 will operate in synchronism. Adjacent the chain 42 is a guideway or support 43 for a sliding plate 44, which latter has a vertically-disposed slotted extension 45 lying adjacent the chain. The chain carries a small plate 46 vertically-movable within the slot of the plate 45, and connected to the sliding plate 46 is an arm or lever 49. The arm is pivoted to a standard 48 carried by the plate 4'} and has rigid therewith a brush 50 and a scraper 52. When the plate 44 is moved in one direction by the action of a chain and the arm 49 is in its depressed position, the scraper 42 is held in engagement with the surface of the drum to remove therefrom the dried material. When. the plate 44 is moved in the opposite direction, thescraper 52 is dropped out of engagement with the drum and the brush 50 is dropped into a trough 51 to move lengthwise of the trough the material which was scraped from the drum and accumulated in the trough previous operation trip of during the last the scraper. Thus, the scraper and brush operate alternately to remove the material from the drum and convey it lengthwise of the receiving trough to a diagonal chute or conduit 54. l

The scraper is so mounted in respect to the distributing nozzle 24 that during the time'the nozzle is delivering liquid to the surfaces of the drums, the scraper is traveling slightly in advance of the sprayer and is scraping off that portion of the material which was delivered to the drum upon the previous sprayingtrip of the nozzle. When 'the scraper and nozzle reach the end of their respective courses, both are thrown out of operation and returned to the opposite end of the drum, during which time the material upon the surface of the drum is thoroughly dried and hardened by the heating action, and rendered uniform in thickness and dense in structure by the crushing action between the two drums. As the sprayer travels longitudinally of the drum during the rotation of the latter, it is evident that the film applied to the drum in the forth of a helical stlrip, all portions of which remain on the dru m during a plurality of revolutions of th'eil-atter, so as to be comprcssed a plurality of times before it is reterial,

' them. At a point directly beneath the line and artificially dried air nto engagement room through a suitable' conduit of tangency of the twodrums, there is provided a conduit 57 servlng to deliver heated with both dru1ns,.said air passing upwardly into engagement with the lower surfaces ofthe drums and then flowing downwardly and outwardly adjacent theunder surfaces thereof, as is indicated by the arrows. The exhaustair preferably passes into engagement with the under surfaces of the troughs to maintain them at the desired temperature.

4 The raw milk in its natural state is delivered from a tank 58 in a refrigerating 59 into. the receptacle 22 of the desiccat-ing and drying apparatus. The drums are internally heated to a temperature ranging from 110 to 150 degrees Fahrenheit, and the warm and artificially dried air is delivered into e11 gagement. with the under surfaces of the drums. The milk is delivered in a very thin film and is permitted to remain on the surfaces of the drums to be thoroughly dried, rolled and hardened during a plurality of revolutions of said drums. The milk becomes transformed to a hard coating, whichwhen scraped oil by the hard scraper 52 or other mechanism, produces. a white,

finely subdivided powder. The powder is removed from thetroughs by the brushes 50,

- and from the conduit 54: it passes to a screen 60 continuously oscillated in any suitable manner. The fine milk powder after having passed through the screen 60-is delivered through a conduit (37 to a receiver (58 in the packing room, Where it is quickly placed in air-tight receptacles. The conduit 67 is heated by a suitable steam jacket 69, which maintains the milk powder at suliiciently high temperature to thoroughly sterilize the same, and the air inthe packing room is also preferably sterilized before being admitted thereto.

In my improved process, the milk almost instantaneously evaporated after being delivered to the surfaces of the drums, but is evaporated at a boiling point of water or milk. If too high a temperature is employed, the albumens may coagulate, t-hc caseins be chemically transformed, and various other changes brought about which would render the milk portion of each of similar to fresh milk.

,any oxidation, decomposition, or

temperature below the ing point of the product insoluble or partially insoluble in water; but by thoroughly evaporating the milk-to a completely dry state while at a temperature 150 degrees, Fahrenheit-and while being repeatedly rolled, no chemical changes are brought about in'the milk vhich would interfere in any way with the free solubility of the latter. It is entirely unnecessary to add sugar, a preservative, or any other substance to the milk before treatingthe sauce,

and the resulting product, therefore, consists of merely the sollds of the milk in such .a-form as to be freely soluble in-watenand when dissolved to form a product exactly The milk is thoroughly sterilized as soon as it leaves the desiccating apparatus and. is then immediately packed in air-tight receptaclesbefore other chemical changes take place. 7

Having thusjdescribed my invention, I

claim as new and desire to secure by Letters Patent:

1. The herein described process of desiccating'liquid or semi-liquid substances, consisting in partially drying the substance upon a surface heated to a temperature from llOto 150 degrees Fahrenheit, pressing the partially dried substance upon said surface by a rolling action to render the coating uniform and to expel the moisture, continuin the heating and repeating the pressing an rolling until the coating assumes a hard, dry, compact form, and scraping the coating from the surface. 2. The herein described processibf desiccating liquid or semi-liquid; substances, consisting in partially drying the substance upon a surface heated-to a temperature below the coagulating point'of the substance, alternately blowing artificial drying warm air upon said substance and pressing the partially rolling action to render the coating uniform and to expel the moisture, continuing the heating and repeating the pressing and roll.- ing until the coating assumes a. hard, dry,

compact form, and scraping the coating ranging from 11.0 degrees to dried substance upon said surface by pressing said layer, substantially as de-' scribed.

4c. The herein described process of desiccating liquid .or semi-liquid substances which consists in spreading same in a thin layer upon a surface heated'below the coagulat substance, subjecting each portion of said layer for a brief period at stated intervals to the action. of a current of artificially dried warm air, and conipress ing said layer immediately after being subjected to said current of air substantially as described' 5/The herein described process of desiceating liquid or semi-liquid substances, which consists in spreading same in a thin layer, continuously subjectlng said layer to a. uniform temperature below 150 degrees Fahrenheit and alternately subjecting same to pressure to expel the moisture and to the action of artificially dried and heated air."

6. The herein described process of producing a dry powder frommilk which consists in spreading fresh milk in a thin layer, subjecting one side of said layer continuously to a temperature below the coagulating point of the milk, and alternately subjecting the other side of said layer to pressure and to the action of a current of heated air until said layer becomes hard and compact, and then reducing said layer to a 'a uniform temperature below-150 F., alter-.

nately subjecting said layer to pressure to expel the moisture then subjecting the layer to the action of air at normal temperature and then subjecting said layer to the action of artificially dried and heatedair until said layer becomes hard and compact and finally reducing said layer to'a powder.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

G. W. VAN DYKE, A. W. WITHERSP OONw 

